fix: harden OpenSim session readiness

crates/metacrate-grid-agent/src/session_tests.rs

@@ -196,6 +196,7 @@ fn test_policy() -> ReconnectPolicy {
     ReconnectPolicy {
         initial_delay: Duration::from_secs(1),
         maximum_delay: Duration::from_secs(8),
+        readiness_timeout: Duration::from_secs(30),
         stable_reset_after: Duration::from_secs(10),
         shutdown_deadline: Duration::from_secs(2),
         jitter_basis_points: 0,
@@ -413,6 +414,38 @@ async fn transport_connection_is_distinct_from_full_agent_readiness() {
     handle.shutdown().await.expect("shutdown");
 }
 
+#[tokio::test(start_paused = true)]
+async fn readiness_timeout_logs_out_and_retries_instead_of_staying_degraded() {
+    let plans = [
+        LoginPlan::Success {
+            after: Duration::ZERO,
+            signals: VecDeque::new(),
+        },
+        LoginPlan::Success {
+            after: Duration::ZERO,
+            signals: VecDeque::from([(Duration::ZERO, SessionSignal::Ready)]),
+        },
+    ];
+    let (backend, stats) = FakeBackend::new(plans);
+    let mut policy = test_policy();
+    policy.readiness_timeout = Duration::from_secs(5);
+    let erased: Arc<dyn GridSessionBackend> = backend;
+    let mut handle = SessionSupervisor::new(erased, policy, 32, 256)
+        .expect("supervisor")
+        .start();
+
+    wait_state(&handle, SessionState::Degraded).await;
+    tokio::time::advance(Duration::from_secs(5)).await;
+    settle().await;
+    wait_state(&handle, SessionState::Backoff).await;
+    assert_eq!(stats.logouts.load(Ordering::Acquire), 1);
+    tokio::time::advance(Duration::from_secs(1)).await;
+    settle().await;
+    wait_state(&handle, SessionState::Online).await;
+    handle.shutdown().await.expect("shutdown");
+    assert_eq!(stats.active_sessions.load(Ordering::Acquire), 0);
+}
+
 #[tokio::test(start_paused = true)]
 async fn shutdown_covers_degraded_authentication_blocked_stopped_and_online_states() {
     let cases = [